Speed control mechanism



SIEET.) CONTROL MEGHANIISM Filed Nov. 23. 1945 3 Sheets-Sheet l Nov. 30,1948. L, DE MARCO M `2,454,914l

SPEED CONTROL MECHANISM Filed Nov. 23, 1945 i 5 Sheets-Sheet 2 MAM/AL Cam-@0L INVENToR. ou/5 DsMAeo 1..,- DE MARCO sfEED: CONTROL MECHANISM Nov. 30, 1948.

A 3 sheets-sheet s Filed Nov. 25. 1945- INVENToR.

o0/5 EMeco' `Arran/#sys Patented Nov. 3, 194g This invention relatestohnpreuemeutsfin speed control -meehuhisms :for ihtetnalueomhueten erreinesfend othereeheuessueh fusfsteem-feneines including turbines, es vu/.ehn as heleopters :end other meehenismsfnndshas dewithfmenhs'ier rendering ,theeuver ehe. moreseneitiueent neeleewlhere inthe HHH.

speed range.

z hef-offthe fehietts of :t

lustrated ein 4the accompanying zidlitwngs, ffm which VFig. `1 -is.fef-sic1e velevational View; partly in sectionyon the :line: =I .+:I offEig-2, -o-cOntml 7meekienism embodying. the: invention, i intein'ledf4 i011 use upon "Diesel engines of:l they Vehicley type.

; neg. k'2 isav 'horizon-tet sectionalwiews pantly on the line 2 -2--of'fEig. v1.

'-Fig. :3' is: azdetailsectional:view-onv the lineir'zr-S of Fig. 2.

.Fig 4 is le1. View similar twintig; lslshowingxaziorm of the :invention intended. for useip-rimeirily iupon Dieselengines of the 'stationa-nytnpe.

f Eigs.v5,=6,f7, and, are diagrammaticl-vews 'of a -modifled totem of the inventioneillustxaatingkthe positions of the parts fordifferentsspeed.settings, and

-f-'l'igfQ is a side elevational fviewf'foftthefmecha nism ofthe latter modification.

'In the drawings .there eisfshown .fait ilu-the ihousingcof :iL-governorurnechanismfor anintnal-eem bustionv engine. The governor-comprises af'shaft .I -I with a lprojecting portion adaptednftoibefs-operatively connected` -with `theinternal.- :combustion engine. "Shaft Il is mountedfinfibeafrings;'Mend I3. y:It carriesa bracketsddfheldgagainst relative rotation'byepin 45. andfhayingmiyot ,which are amounted arms `1 1- gcafrryingeent iugal weights I-8,V the weights f irhavinggubeaJ-,ring surfecesIS which engage rollersZII-'Qnaslideil is providedwith eers fZfZ- whiehf tandlerthee ms I1 and impart rotannftherefte Asthe sneedrnf rotatienfnereuses 'thetheeirinefsurienesaci against rol-1ere 20.and ier-.Ge s1de- 2I;.to.th right, as'uieWedin-Fiefz. @'iIh'srressure-fistransmitted that j to albnllfgbeering 23 which hearsagainstarsocket coller ZILthat receiyes `one end tof. I ecolfspringxzz, the opposite .end V of which engages'a'gueinst en abutment plate 26. e

-inthe housing- I-II xthere is mounted @transverse roekgshet 2.1 Vto whihis xed vanyokegZ that carries pins'lonnollers, y29 ,which runY in v.et lgrooueu. in the neuer-:14. O buiuusly, @IS-"the helmut-.metes alongv Ithefshat. I I Ibecause of; pressure exertedV by th e1idefv2l er-..retum pressure fexehted 'uu the se he 25, thegfeheftflwill jeSei-lluteftheirI en@ te, h governor eehsttueteu, per Se; -euue minette thegureseht inuentieu 2A Simileueenf sttuetien fully desembee uudselemedihemu een eine enpleatienerel-NO- 592,-1-19h1edMey- ,51 9&5-

Ilrasnsyerse shafft a21 fprojects forwardly from th nusnenesnfiewedin they :dta- Wines and eX- uehj supplemental housine-or casing-e9 ewes anrimerily lto protect uthe parts @eti-hiet Qsture, yclust and :othenforeen matter. Withinmesingq 9 Ymenu nl is mounted to turn fueelyfnbellt thenxs ofY the shaft. Provision 4,iS matie io he se ine ofthis-eem -i n diff;erent angular Qs onsffite throwiihene limited hik-a slot 32 in the cam receiving a. machine screwi thatis threnclecl zntofthe housing 5H).

','The noeensf#illustratedy in Figs. '1 and 2 for manuallysetting ca'm .31 in any :selected position consistszof-a,-transverse rock `shaft 34 having. :a Grainkretojwhich 'isfattached a link- 36 that may eliterid tof. 'any location :convenient for operation. Qnthe opposite end of shaft 34 there ymay abe i'ixedfanother crank "311 having an enlargedend workingg-linuthevcavity of etv tlf-shaped rbracke't which isasecured to, ormagdeinteg-ralwith, camel mhecem is. shown 'inrEig 1 at one limit oflits motion/corresponding :to the :idle position Lof the engine. As theflinkru is moved toward the tleft,

clockwise. When movedV .in 'this direction to the limit,oumotionipermtted :by the slot '32 the cam will Ilee-setifor the gmaxiinurnf speed of athe e. engine. Qn theisl'leuft;f 'ily .iexterio'rly of the come 3l: there is pinned aanr'arnnf which,V at its 4louter extremity, isvv mentoratedI :to --oseillatabl'y fsupport- "the middle par-t of. al'shortshajftf I @On the-innerend ofthis shaft there is p innedeJ lever. arm ft2, fatethe-outer end of which is a roller follower 43 which runs inf. a @Camelot e414 in. neemmember el. int the fem-amd end @of shafft-Mand on the opposite Aside rm lthere is pinnedy a. second vlever arm eg anm- 9 2;- gthe shaft.; 4 :mel` the; vanni a4-5 teeether gestiti-tte, a bell mank lever, vthe,@motel point pfgsthich movSxWith the swinging; 121m? 40.

Lever arm 45 carries an enlargement at its outer extremity which engages between the legs of a U- shaped end portion on a crank 49 that is formed integral with a sleeve l! which surroundsand is rotatable with respect to shaft 21. Uponsleeve 50 outside the casing 30 there is clamped a crank 5| with an eye at its outer end. A yoke 52`straddles crank 5l, the two parts being pivotally conconstitutes part of a link connection which may include a nected by means of a pin 53. Yoke 52 turnbuckle 5,4 for adjustment purposes. All of these parts 49, 50, 5l, 52, 53 and 54,*together are referred to hereinafter as'throttle means.` They operate a fuel regulator, not shown, in the fuel line of a Diesel engine. i

In the Fig. 4 construction the cam 6l is free to turn vabout the axis of shaft 21 within casing 60', and is adapted to be shifted to any desired position by a handleS'I directly connected to or formed integral with the cam and projecting through a slot 68 in the periphery of the casing. r

Slot and pin means 62, 63 limits the throw of ,the cam, and a nut, not shown, may be threaded onto pin 63 for locking the cam in any position of adjustment. 64 is a V control arm secured to shaft 21 and corresponds in function to the arm 40 of the rst described form ofthe invention. At'its extremity it carries a pivot 65 `uponr which is mounted a bell crank lever having lever arms 69 and 16. Lever arm 69 carries a roller follower'1l which runs in a cam slot having two arcuate portions 12 and 13 connected by an eccentric portion 14. Lever arm runs through a slot in the perimeter of the casing 60 and has an operating -link connected with it, which link extends to-or forms part of the throttle mechanism of the engine. f Y Operation-Figs' l, 2 and 3 show an'application of the invention to control mechanism for an internal combustion engine of a type designed for. operation of course be driven by the engine, and as conventionally constructed it respondsy uniformly to speed variations throughout its speedlrangepin other `words `from its idling speedup 'to its in# tendedrunning speed. 'A governor with a'uniform effect throughout its speed range cannot be made sensitive to small variations in the critical speed range, that is at and near the desired running speed, because if it wereso made the governor movement over the complete range would be so' great as to'be prohibitive. Inthe present invention the response of the control mechanism to speed changes throughout the greater part ofthe speed range of the engine is relatively small, while in the critical range at and near the running speed of the engine the control mechanism responds to relatively slightspeed variations, and thus an accuratecontrol of speed in that' range results.

In Diesel engines a rich mixture is required for acceleration, while a somewhat leaner mixture gives optimum results after the engine has attained running speed. My control mechanism as illustrated in Figs. 1, 2 and 3 is designed to automatically accomplish this result. The position of atvariable speeds. The governor must ping a rich mixture into the engine,

4 parts in Fig. 1 is for idling speed. In order to accelerate the engine to running speed, the operator moves link 36 gradually to the left, which operates through cranks and 31 to move cam 3l clockwise. The rst effect of such movement is to cause follower 43 to run onto the shorter radius arcuate portion 56 of the cam, thereby swinging the hell crank lever 42, 4I, 45 clockwise and Amoving V-crank 49 counterclockwise. The throttlemeans 49, 56, 5I, 53, 52 and 54 thereby moves to open the fuel regulator somewhat, feedwhich then accelerates. As the engine speed increases shaft 21 will turngradually in the clockwise direction,

j carrying along with it control arm 4D, and because of the interconnection between lower arm 45 and crank 49 this will impart a clockwise movemer-1t to sleeve 56 which will transmit motion to the throttle means, gradually reducing the opening of the fuel valve. As soon as the engine reaches the speed for which the cam 3l is set by the operator the'follower 43 will again ride into the eccentric part 48 of the cam, when the bell crank 42', 4l, 45 will turn counterclockwise, thereby giving a rapid clockwise movement to sleeve 56 and reducing the richness of the mixture to the valve needed for running at the speed called for by the particular cam setting.

Now, should the load be increased, tending to reduce engine speed, shaft 21 will turn counterclockwise, moving pivot 4| 4downward and to the left and drawing follower 43 into the portion 46 of the cam. This will quickly turn crank 49 counterclockwise, opening the fuel valve to enrich the mixture and thereby increase the speed until the follower 43 again moves into the eccentric part of the cam and the speed is brought back to that for which the cam is set. On the other handit the `load upon the engine is de- ,1 creased the engine will tend to speed up and the shaft .21 will turn clockwise, causing control arm 46 to move follower 43 into the longer radius yarc 41 of the cam, which vwill turn bell crank 42, 4|, 45 counterclockwise and transmit clockwise move- .A ment to crank 49, whereby the fuel valve will be moved toward closed position an amount sufficient to reduce engnespeed to the point where the arm 40 will again return the follower 43 to the eccentric part of the cam, resulting in a return to the speed for which the cam 3| is set, l `While I` have shown the arcuate portions 46 and `41 of the cam as centered upon the axis of shaft 21, so that the rate of rise of those portions of the cam' is zero, it will be appreciated that those portions :need not'necessarily be arcs of circles, and if they are arcs of circles they need not necessarily be centered upon the same axis or upon the axis :of shaft 21. The object of the cam and follower construction is to modify the effect of the-governor action upon the throttle means, and to vary this modification to suit different conditions iswithin the purview of the invention.

The form of the invention illustrated in Fig. 4 is intended foruse upon internal combustion engines or other engines, particularly stationary engines which are operated ordinarily at a predetermined running speed. The cam 6l is set at a desired speed by manipulation of handle 61, and may be locked in that position if desired. As illustrated the said setting is for an intermediate speed, and the control mechanism is shown in the running position for that Speed. Now, in case the operator desiresv to decelerate to idling speed, he will vgra-sp'handle 61 and swingcam Gl counterclockwise as far asthe pin and'slot connection terfiy or throttle to the necessary extent to attain and hold that speed.

Having thus described my invention, I claim:

1. In engine control mechanism, a control member movable in a predetermined path only, a bell crank lever pivoted to said control member, a throttle operating element articulated with one arm of said bell crank lever, the other arm thereof carrying a follower, and cam means engaged by said follower, whereby the effect upon said throttle operating element of a given movement of said control member may be modified by cam contour.

2. Engine control mechanism according to claim 1, wherein said control member is an arm swinging about a xed axis.

i 3. Engine control mechanism according to claim l, wherein said control member is an arm swinging about a fixed axis, and said cam means is adjustable about the same axis.

4. In engine control mechanism, a governor adapted to be driven by the engine, a control member movable in response to changes in governor speed, a bell crank lever pivoted to said member, a throttle operating element articulated with one arm of said bell crank lever, the other arm thereof carrying a follower, and cam means engaged by said follower for maintaining a given relation between said bell crank and said control member while the latter moves in one direction toward a predetermined critical engine speed setting and for swinging said bell crank on said member in response to small speed variations in the neighborhood of said critical speed.

A5. In engine control mechanism, a governor adapted to be driven by the engine, a rock shaft arranged to turn in response to changes in governor speed, a control arm fixed upon said shaft, a bell crank lever pivoted to said control arm, a throttle operating element articulated with one arm of said bell crank lever, the other arm thereof carrying a follower, and cam means engaged by said follower for maintaining a given relation between said bell crank and said control arm while the latter moves in one direction toward a predetermined critical engine speed setting and for swinging said bell crank on said control arm in response to small speed variations in the neighborhood of said critical speed.

6. In engine control` mechanism, throttle means, a manually operated cam settable for different engine speeds, a governor` adapted to be driven by said engine, control means responsive to said cam when advanced to a higher speed setting for initially manipulating said throttle i means, said control means being responsive also to said governor acting through said cam for continuing said throttle manipulation regularly until the engine attains the speed for which said cam is set, and then functioning rapidly in either direction to oppose small speed fluctuations and hold the engine speed substantially constant.

'7. In combination, throttle means for an internal combustion engine, a cam settable for a selected engine speed, said cam having a uniform rate of rise portion and a rapid rate of rise portion at one end of said uniform portion, a governor adapted to be operatively connected with said engine, control means actuated by said governor comprising a follower for said cam adapted to actuate said throttle means at a uniform rate while the follower runs on said uniform cam portion and to actuate said throttle means more rapidly when the follower reaches said rapid rate of rise portion of the cam, whereby 8 said throttle means is sensitive to small speed fluctuations in the neighborhood of said selected speed.

8. In combination, throttle means for an internal combustion engine, a cam settable for a selected engine speed, said cam having two portions, each with a uniform rate of rise, said uniform portions being connected by a rapid rate of rise portion, a governor adapted to be operatively connected with said engine, means actuated by said governor comprising a follower for said cam adapted to actuate said throttle means at a uniform rate while the follower runs on either of said uniform cam portions toward the said rapid rate of rise portion and to actuate said throttle means more rapidly when the follower reaches said Arapid rate of rise portion, whereby said throttle means is sensitive to small speed variations in either direction from said selected speed.

9. In combination, throttle means for an internal combustion engine, a cam settable for a selected engine speed having two circular arcs of different radii with a common center and connected by an eccentic portion, a governor adapted to be operatively connected with said engine, means actuated by saidgovernor comprising a follower for said cam adapted to actuate said throttle means at a uniform rate while the follower runs in one of said circular arc portions and to actuate said throttle means more rapidly when the follower reaches said eccentric portion of the cam, whereby the control of said throttle means is sensitive to small speed fluctuations in the vicinity only of said selected speed.

lo. In speed control mechanism for an internal combustion engine, a governor adapted to be operatively connected with said engine, a shaft oscillatable in response to speed changes in said governor, a cam pivoted about the axis of said shaft and settable for a selected engine speed, said cam having an arcuate portion centered at said axis and an eccentric portion at one end of said arcuate portion, an arm secured to said shaft, a lever pivoted on said arm having a follower running on said cam, and throttle means operatively connected with said lever.

l1. Speed control mechanism according to claim l0, wherein said throttle means comprises an element oscillatable about said axis.

12. In speed control mechanism for an internal combustion engine, a governor adapted to be operatively connected with said engine, a shaft oscillatable in response to speed changes in said governor, a cam pivoted about the axis of said shaft and settable for a selected engine speed, said cam having two arcuate portions of different radii both centered at said axis, said arcuate portions being connected together by an eccentric portion, an arm secured to said shaft, a lever pivoted on said arm having a follower running on said cam, and throttle means operatively connected with said lever.

13. In speed control mechanism for an internal combustion engine, a governor adapted to be operatively connected with said engine, a shaft oscillatable in response to speed changes in said governor, a cam pivoted about the axis of said shaft and settable for a selected engine speed, said cam having two arcuate portions of different radii both centered at said axis, said arcuate p0rtions being connected together by an eccentric portion, an arm secured to said shaft, a bell crank lever pivoted at an intermediate point to said arm, one end of said lever having a follower running on said cam, and throttle means operatively connected with the opposite end of said bell crank lever.

14. Speed control mechanism according to claim 13, wherein said throttle means comprises an element oscillatable about said axis.

15. In speed control mechanism for an internal combustion engine, a governor adapted to be operatively connected with said engine, a shaft oscillatable in response to speed changes of said governor, a cam pivoted about the axis of said shaft and settable for a selected engine speed, said cam having an intermediate eccentric por tion connecting two arcuate portions of different radii, control means responsive to governor` action comprising a follower running on one of said arcuate portions of the cam when the latter is set for a higher speed and on the other arcuate 10 portion when the cam is set for a lower speed and engaging said eccentric portion in the critical speed area, and throttle means operatively connected with said control means, whereby the throttle means is more sensitive to speed luctuations in the critical area than elsewhere. l

LOUIS DE MARCO.

REFERENCES CITED rlhe following references are of record in the le of this patent:

UNITED STATES PATENTS 

